The pilot did not request CARS services after usual business hours, thereby depriving himself of services such as flight monitoring, which would have allowed the occupants of the aircraft to be rescued more rapidly. When the engine was shut down on take-off, climb performance was negative, as indicated by the manufacturer. The engine was shut down at the most critical time in the initial climb, between rotation and acceleration, causing the aircraft to crash. The exhaust muffler on the right side of the engine and the exhaust pipe became disconnected because two stainless steel collars were installed on the far aft side of the No. 5 cylinder exhaust pipe to prevent the exhaust muffler from coming into contact with the No. 5 cylinder baffle. The technician did not deem that there was a risk in making that modification. Installation of the collars was not prescribed in the modification for Supplemental Type Certificate SA-240. Also, the way the collars were installed was inconsistent with quality standards and the manufacturer's instructions, thus contributing to a considerably greater risk of fire. In 1997, three different individuals held the position of Director of Maintenance. Due to frequent staff changes, it was difficult for company personnel to properly follow up on aircraft records. The aircraft flew a lot of hours and were not to be kept on the ground very long for maintenance. In this remote area, Transport Canada inspections are infrequent, which is confirmed by the information found on file. In addition, correspondence between the company and Transport Canada was almost exclusively of a bureaucratic nature. A review of the aircraft log-book showed that the aircraft had been operated with uncorrected deficiencies. The record keeping and files for the aircraft were incomplete and inadequate.Analysis The pilot did not request CARS services after usual business hours, thereby depriving himself of services such as flight monitoring, which would have allowed the occupants of the aircraft to be rescued more rapidly. When the engine was shut down on take-off, climb performance was negative, as indicated by the manufacturer. The engine was shut down at the most critical time in the initial climb, between rotation and acceleration, causing the aircraft to crash. The exhaust muffler on the right side of the engine and the exhaust pipe became disconnected because two stainless steel collars were installed on the far aft side of the No. 5 cylinder exhaust pipe to prevent the exhaust muffler from coming into contact with the No. 5 cylinder baffle. The technician did not deem that there was a risk in making that modification. Installation of the collars was not prescribed in the modification for Supplemental Type Certificate SA-240. Also, the way the collars were installed was inconsistent with quality standards and the manufacturer's instructions, thus contributing to a considerably greater risk of fire. In 1997, three different individuals held the position of Director of Maintenance. Due to frequent staff changes, it was difficult for company personnel to properly follow up on aircraft records. The aircraft flew a lot of hours and were not to be kept on the ground very long for maintenance. In this remote area, Transport Canada inspections are infrequent, which is confirmed by the information found on file. In addition, correspondence between the company and Transport Canada was almost exclusively of a bureaucratic nature. A review of the aircraft log-book showed that the aircraft had been operated with uncorrected deficiencies. The record keeping and files for the aircraft were incomplete and inadequate. By not requesting the services of the CARS observer/communicator after usual business hours, the pilot deprived himself of the services normally provided, including flight monitoring, which would have allowed the occupants of the aircraft to be rescued more rapidly. The aircraft could not maintain a sufficient rate of climb when the right engine was shut down at the most critical time of the flight, between rotation and acceleration, thereby causing the crash. Two stainless steel collars installed on the far aft side of the No. 5 cylinder exhaust pipe caused the exhaust pipe to become disconnected. This modification was inconsistent with the exhaust muffler (heat exchanger) installation procedures. The company had three different Directors of Maintenance in 1997, and that position was vacant on the day of the accident. An inspection of the records and files for the aircraft revealed several deficiencies in records management. The persons in charge of maintenance authorized the aircraft to be used while deficiencies had not been corrected. Transport Canada had not made regular audits of the company since 1992. Only one review of the maintenance department was conducted, in September 1994. The last review of the maintenance department was conducted after the accident, in February 1998, and several deficiencies concerning the maintenance department and the company were found; the review resulted in the suspension of the company operating certificates.Findings By not requesting the services of the CARS observer/communicator after usual business hours, the pilot deprived himself of the services normally provided, including flight monitoring, which would have allowed the occupants of the aircraft to be rescued more rapidly. The aircraft could not maintain a sufficient rate of climb when the right engine was shut down at the most critical time of the flight, between rotation and acceleration, thereby causing the crash. Two stainless steel collars installed on the far aft side of the No. 5 cylinder exhaust pipe caused the exhaust pipe to become disconnected. This modification was inconsistent with the exhaust muffler (heat exchanger) installation procedures. The company had three different Directors of Maintenance in 1997, and that position was vacant on the day of the accident. An inspection of the records and files for the aircraft revealed several deficiencies in records management. The persons in charge of maintenance authorized the aircraft to be used while deficiencies had not been corrected. Transport Canada had not made regular audits of the company since 1992. Only one review of the maintenance department was conducted, in September 1994. The last review of the maintenance department was conducted after the accident, in February 1998, and several deficiencies concerning the maintenance department and the company were found; the review resulted in the suspension of the company operating certificates. A modification to the cabin heating unit inconsistent with the manufacturer's recommendations and aviation regulations caused an engine fire in the right engine cowl during the initial climb. The pilot shut down the engine, but the aircraft could not maintain a positive rate of climb and crashed to the ground.Causes and Contributing Factors A modification to the cabin heating unit inconsistent with the manufacturer's recommendations and aviation regulations caused an engine fire in the right engine cowl during the initial climb. The pilot shut down the engine, but the aircraft could not maintain a positive rate of climb and crashed to the ground. As a result of the TSB investigation, Transport Canada took immediate action by suspending the Aircraft Maintenance Organization certificate of Air Nunavut Ltd.Safety Action As a result of the TSB investigation, Transport Canada took immediate action by suspending the Aircraft Maintenance Organization certificate of Air Nunavut Ltd.